planner

## Creating an Iterative Alignment

Iterative Alignment dialog box

When you click the Iterative button from the Alignment Utilities dialog box (Insert | Alignment | New), Planner displays the Iterative Alignment dialog box. This dialog box provides a way for you to three-dimensionally "best fit" the measured data to the nominal points (or surfaces, if available).

The resulting iterative alignment coordinate system origin is approximately located at and oriented with the CAD coordinate system, even if the set of features used is located and oriented somewhere very different. This is much like an automotive system, in the sense that all the feature on all the parts of the automobile's body are defined in terms of a single global coordinate system, even if they are physically located or oriented far away from that coordinate system. The CAD coordinate system serves the same function for the iterative alignment as the car body's global coordinate system.

An iterative alignment requires at least three features to be measured. Certain feature types, such as points and lines, have poor three dimensional locations. If one of these types of features is selected, additional features are needed to provide accurate measured data.

- The first set of features establishes the orientation of the normal axis of the current workplane by fitting a plane through the feature centroids. At least three features must be used in this section (LEVEL - 3 +).

- The next set of features rotates the defined axis of the workplane to the features, fitting a line through the features. At least two features need to be used in this section (ROTATE - 2 + ).
  If no features have been marked, the alignment will use features from the LEVEL section. (The two features used from the LEVEL section are the second and third from last feature.)

- The last set of features translates the part origin to a specific location (SET ORIGIN - 1 ).
  If no features have been marked, the alignment will use the last feature from the LEVEL section.

More:

Understanding Iterative Alignments

To Create an Iterative Alignment

Description of the Iterative Alignment Dialog Box